The Mediterranean Sea supports high levels of biodiversity and complexity but is facing increasing human pressures, so that strategies to protect and recover its ecosystems must be a priority in environmental policies. Benthic cartography represents the first step of marine spatial planning for the proper management and protection of our sea. Univocal habitat classification systems are thus needed to map, monitor, and inventory marine habitats, and to guarantee common and shared frames for a harmonized interpretation of the Mediterranean habitat types.

This paper reviewed the existing classification systems of marine benthic habitats, to discuss the process of revision and updating of one of the first system development under the Barcelona Convention (BC) in 1998 and adopted by all the Mediterranean countries.  The BC classification was revised including the new habitats discovered in the last 30 years, and consistently with the criteria used to revise the European Nature Information System (EUNIS), which is a comprehensive pan-European system for habitat identification. The updated BC classification is hierarchical with 5 levels, which allows representing the most suitable habitat level with respect to the restitution scale of the map.

The authors state that the new updated BC classification system has been used for the selection of reference marine habitats that support two fundamental processes of environmental management: 1) identification of Specially Marine Protected Areas according to the SPA/BD Protocol of Barcelona Convention; and 2) selection of habitats to be monitored, as requested by the Integrated Monitoring and Assessment Programme and the European Directives. As a result, the new list of reference habitats, selected because of their high ecological and conservation value, contains 267 habitats, corresponding to 68% of the total habitats listed in the updated BC classification.

Montefalcone et al. (2021) A review of the classification systems for marine benthic habitats and the new updated Barcelona Convention classification for the Mediterranean. Marine Environmental Research 169: 105387.